M2T

m2t is a filename extension used for MPEG-2 transport stream files, typically associated with HDV video recordings. An M2T file contains a transport stream that carries one or more programs, usually encoded with MPEG-2 video and accompanying audio streams. The streams are packaged in the MPEG-2 transport stream format, commonly using 188-byte packets.

Historically, m2t files are produced by HDV-compatible camcorders and equipment. HDV, a codec and recording mode developed in the early 2000s, used MPEG-2 video with MP2 or AC-3 audio and stored the data as transport streams with the .m2t extension. These files may represent single clips or concatenated segments from a longer recording, depending on the camera and workflow.

Compatibility and handling vary by software. Many video editors and media players support m2t natively or via standard import filters for MPEG-2 transport streams. In some cases, users may convert m2t files to more common formats (for example, MPG or other MPEG-2 formats) for easier editing or playback. Tools such as media players, video converters, and non-linear editors commonly offer options to open, import, or transcode m2t streams.

Related formats include M2TS, which also denotes a MPEG-2 transport stream but is used in Blu-ray Discs and AVCHD, and MTS/M2TS variants used by different device ecosystems. While m2t is strongly linked to HDV, M2TS is more widely applied in contemporary high-definition disc and storage contexts. See also MPEG-2 transport stream, HDV, AVCHD, and related container extensions.